Thermometer.



PATENTED MAY 29, 1906.

No. 'S2-1,848.

M. E. BEGTON. THERMOMETER. APPLIOATION FILED JUNE 9,1905.

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wi nemen MILLARD F. BECTON, JERSEY CITY, NEW JERSEY.

THERMOMETER.

Specification of Letters Patent.

Patented May 29, 1906.

Application filed June 9,1905. Serial No. 264,518.

To all when@ it may concern:

Be it known that LMILLARD F. BEcToN, a citizen of the United States of America, residing at Jersey City, in the county of Hudson and State of New Jersey, have invented new and useful Improvements in Thermometers, of which the following is a specification. f

The invention relates to an improvement in thermometers, and particularly to clinical thermometers, wherein accuracy is of an essential importance.

The main object of the present invention is the production of a thermometer of the class described which shall be accurate under all conditions 'and especially adapted for the use mentioned, being capable of thorough antiseptic cleaning without interfering with the marking or accuracy of the instrument.

The invention in its preferred form will be described in the following specification, with particular reference to the accompanying drawings, in which Figure l is a front elevation of a thermometer constructed in accordance with my invention. Fig. 2 is a perspective of a scaletube used in my invention. Fig. 3 is a perspective of the backing-strip used in my construction. Fig. 4 is a section on line 4 4 of Fig. l. Fig. 5 is a perspective view illustrating a modified form of scale-strip. Fig. 6 is a transverse section through a thermometer using the modified form of strips. Fig. 7 is a transverse section through the bulb on line '7 7 of Fig. l.

Referring to the drawings, my improved thermometer comprises a bulb l and tube 2, the bore of the latter communicating with the mercury-space of the bulb, as is usual in devices of this character.

The tube is approximately triangular in transverse section, having the mercury-bore 3 about central thereof, immediately in rear of the pointed edgev of the tube. The tube directly in rear of the mercury-bore is formed with a longitudinally-arranged opening 4, preferably segmental in section, with the chord edge adjacent and parallel with the similar edge of the tube, the arcuate edge being next the mercury-bore. The scale-strip 5 comprises a hollow tube-like strip, having such exterior dimension as to 'fit snugly within the opening 4 in the tube, terminating slightly below the upper end of the tube. The face or rounded surface of this scalestrip is marked with the desired scale-lines,

made of light-reflecting as at 6, and the scale-strip inserted within the opening 4 in the tube. i

' It is desirable, however, that means be provided whereby to facilitate the reading of the scale, and to this end I insert within the bore of the scale-strip what I term a backingstrip 7 8, similar in contour to the scale-strip and of a sectional dimension to fit snugly therein. The backing-strip is preferably glass or may be made of any light-refiecting material. vertical edges 9 of the backing-strip are preferably lined in some bright color to act as a finder and direct the eye immediately to the scale on the strip 5.

In the modified form shown in Figs. 5 and 6 the scale-strips are two in number, each including one-half of the single scale-strip used in the preferred form. These strips 10 are placed side by side, thereby forming practically a continuous scale-strip, and are inserted within the opening 4 in the tube 2, as illustrated in Fig. 6. In this instance the remote edges l1 of each of the strips 10 are lined in color, and the stripsthemselves may be of luminous or brilliant glass or may be enameled in colors.

The bulb l of my improved thermometer is preferably oval in transverse section and may be smooth or ribbed lengthwise, as desired, thereby providing forgreater sensitiveness of the instrument.

By using a segmental tube as the scalestrip I am enabled to provide the maximum of surface in the minimum of direct transverse space', whereby to provide additional surface for the scale-mark. The backingstrip will reflect light onto the scale and mercury column, rendering the instrument easily readable in dim light. The colored lines on edges of the backing-strip serve as a finder, it being understood that the thermometer-tube itself, owing to its sectional form, is of high magnifying power and that the colored lines are effective in determining The I IOO the location of the mercury with relation to IIO Having thus described the invention,what I claim is` 1. A thermometer formed with a mercurybore and with a second bore in rear of said mercury-bore, a hollow scale-strip inserted in said second bore, and light reflecting means V.within said hollow strip.

2. A thermometer formed with a longitudinally-arran ed bore in rear of the mercury column, a hol ow scale-strip within said bore, and a light-reflecting strip inserted within and fitting the hollow bore of the scale-strip.

3. A thermometer formed with a longitudinal bore in rear of the mercury column, a hollow l scale-strip fitting within said bore, and .a light-reflecting backing-strip within the scale-strip, the edges of said backingstrip being colored contrastingly with the remainder ofthe strip.

4. A thermometer formed with a longitudinal-bore in rear of the mercury column, a semicylindrical hollow scale strip fitting within said bore, and a light-reflecting backing-strip fitting snugly within the scale-strip, the edges of the backing-strip being colored.

In testimony whereof I affix my signature in presence of two witnesses.

MILLARD F. BEoToN.

Witnesses:

J. F. ARNOLD, L. A. OBRIEN. 

